I'm entering this in the Green Challenge and the Epilog Challenge. If you like what you see, please vote for me!My previous green fire instructable, The Spirit Lantern (Green Fire 2.0), was entertaining and educational to make, but it raised a couple of concerns:
1) A methanol flame is hot (from 500˚ C up to ~1900˚ C under some conditions according to online sources - I've been able to bend borosilicate tubing over a methanol flame, so think 820˚ C/1500˚ F), and an open flame is a fire hazard
2) One of the combustion products, diboron trioxide, is a white powder that settles all over everything, and makes a mess
Although this instructable doesn't entirely solve these problems, it mitigates them somewhat, and (in my opinion) results in an end product that's both more versatile and more aesthetically pleasing. That said, this is not something you want to leave unattended (in most of it's incarnations - caveat: see "safe mode" below), and there is still some diboro trioxide that escapes the lamp, so it still might be best described as "outdoors fun." I present it to the discerning ladies and gentlemen of the Instructables community however, as an entertaining part of any soiree where children are well-behaved and supervised, or (better still) in bed, and the only thing imbibing alcohol is the lamp itself. In other words, use discretion.
A note on the photography: photographing the various flames/light sources while keeping the lamp details visible is seriously hard. If you'd like to see what the green fire looks like in it's natural state, without other incandescent light throwing off the color balance (and vice versa), check out my previous green fire instructable, referenced above.
Later:
Hey! I got written up in Hack a Day! They're a little less sanguine about the methanol version due to the temperature of the flame and the fact that the glass is not borosilicate. So let me address that concern, at least a little: with a thicker wick (like 1/2"), the flame temperature of ~820˚ C I achieved was at the tip of the inner cone of the flame, the hottest part. This allowed me to bend a very thin borosilicate pipette. To get a higher temperature than this, you would need to have a much more sophisticated set-up, including a much better means of controlling combustion. The glass of this lantern doesn't get anywhere near that hot - most of the heat is dissipated by the time it reaches the glass. However, I do get the concern, and so I'd like to emphasize that those who feel freaked out about a methanol lamp can make a cooler burning (albeit less purty) lamp using isopropyl alcohol (rubbing alcohol), and please do not leave this unattended. For those looking for flame temperatures of various fuels, check out the Wikipedia article on the subject. Not to harp on the subject, but the temperature of a candle flame can be over 1400˚ C. Okay, now I'll shut up.
Still later:
I've written a mod/add-on for this that allows you to heat water (or food). It's called the Spirit Samovar! Check it out!
Step 1: Things you need
A relatively shallow financial sea and a somewhat ... for lack of a better word, colorful, history, have left me with the resources of an indulged 13-year-old. Therefore, this instructable uses no tools more exotic than a cordless, electric drill, and the materials are either inexpensive or free. The materials, in particular, are a sort of scavenger-hunty affair, as many of the items used are not very standardized:
Materials:
Snapple or Honest Tea Bottle (tea/juice removed) (or size equivalent e.g. some 10 oz Jelly/Jam jars)
Eden Organic Bean Can - 12 oz. (sans beans) (or size equivalent)
Slightly larger can from Chili/Soup - pull top e.g Campbell's Chunky (sans chili or stuff) (or size equivalent)
4 Socket (Allen-wrench) button-head bolts (M6 X 8mm or equivalent)
4 Hex nuts (M6 or equivalent)
3 6-32 thread X 1" machine screws (must fit standoffs below) - I originally had this as 3/32" in error
3 1/4" OD, aluminum, 6-32 thread, round, female/female standoffs/spacers (must fit machine screws above) I originally had this as 3/32" in error
1 old-fashioned style clothes pin (or wooden or ceramic drawer-pull, lamp finial, or equivalent)
1 small screw that fits clothes pin (or substitute)
1 sampler-sized jelly jar (or equivalent)
lamp wick
wood stain
boric acid
methanol (Heet - yellow bottle from an auto supply shop)
or denatured alcohol (somewhat less green flame)
or isopropyl alcohol - 91% (for non-green variety of flame)
or votive candle (for safer, non-green flame)
or LED votive ("Safe Mode")
acetone/xylene/naptha/other non-polar solvent (optional)
lead-free solder
Tools:
Hacksaw
Utility knife
glass cutter
glass cutting jig
center punch
paper hole punch
electric drill
electric burner/toaster oven (not to be used for food again) and/or
propane or butane torch (optional, depending on patience)
cheapo files
sandpaper (120, 220 and 400 grit)
And of course, as no instructable is complete without warnings: Alcohol flame = up to 1000˚ Celsius (very hot) so lamp is very hot when lit. Concentrated alcohol vapors are explosive. Boric acid, in VERY large doses, or with regular ingestion/inhalation, may be a health/reproductive hazard, particularly for males (However, to reference the conversation from my last Green Fire instructable, boric acid itself is only slightly more lethal than table salt, "nu salt," borax, or baking powder). Methanol, denatured alcohol and isopropyl (rubbing) alcohol are all toxic. Do not ingest. You will be cutting metal, and the tiny pieces sticking out from the ragged edges of the cut metal are like little knives that will pierce most gloves. Making big alcohol-burning stoves out of big jars is stupid. Don't do it. Jars are don't do well with extreme temperature gradients, and if your's breaks while lit, you will end up with a flaming pond of methanol, and no, you can't just "stomp that out." Let's see, did I forget anything? Sharp, hot, don't eat, don't poke, no stomping, outdoors fun, not a child's toy. I think that covers it.
Step 2: Cut Glass
The first step is removing the top and bottom of your chosen bottle to make the glass body of the lamp. There are many ways to cut bottles. The easiest seems to be that popularized by Green Power Science on Make.com. I don't share his success rate, but I also have a pretty much free jig with a $3 glass cutter. The basics are as follows:
1) means of holding bottle more or less in place while you rotate it
2) means of holding glass cutter in place while you press it against the rotating bottle
3) for jury-rigged jigs like mine, draw a line with a sharpie as though it were the cutter, then follow the marker line with the cutter - this limits waver, and increases the odds of success.
I've included a model of my jig, which I created using Autodesk 123d. I think it probably gets the idea across better than my pictures do. In my recent instructable on glass cutting, I discuss my jig as well as some other observations I've made on cutting bottles this way.
Stubborn labels and printed dates can be removed with acetone, xylene (Goo Gone), Naptha (lighter fluid), or other solvents. Slightly less effective, or at least less rapid, but certainly more environmentally-benign, is vegetable oil, followed by dish detergent. The vegetable oil acts as a non-polar solvent, and the detergent allows the oil-glue mixture to be washed away. You may need to use a scraper of some kind, like a single-edged razor, or even the back of a butter knife. I would strongly recommend that you clean the bottle before cutting, but if you try to clean after cutting, definitely sand the edges before getting the glass wet and oily, unless you enjoy bleeding.
Once you have scored the bottle, if you follow the GPS method referenced above, you will need to gently shock the glass by subjecting it to alternating streams of near-boiling water and cold tap water. You do not want to dip the bottle in either of these, as this stresses a much larger surface of the glass, and it is likely to go rogue on you and ignore the line you so lovingly inscribed on its surface. Just pour a thin stream over the line you cut, and make sure that you have something soft for the cut-off piece to fall on when it separates from the main mass. On a side note, the little black flecks in the sink in the picture above are tiny shards of glass with sharpie on them. Scoring the bottle will tend to generate these, and they will pop off at odd intervals throughout this process. Safety glasses are a good idea, and if you do this in a sink, be prepared for a little cleanup afterwards.
The bottle I used (the Honest Tea one) is shown in the last few pictures. I decided to go back and do the actual cutting again so that I would have the steps more explicitly described for those who haven't done this before. I use a 365 (Whole Foods brand) 10 oz. Organic jelly jar as an example, which isn't quite as snug a fit as the Honest Tea or Snapple bottles, but will work in a pinch.
After making the first cut, you will have a very sharp edge to work with. I would recommend that you sand this cut a bit before you try to cut the other end off. That way you won't accidentally cut yourself, and if your jig is wood, like mine is, the bottle won't be as likely to bite into the wood of the jig. Alternatively, you can score both lines with the cutter, and then finish them with in the sink. I show that approach in the pictures here.
Shock the glass as above - however, realize that the second cut is a bit trickier than the first (in my experience). I suspect that once one end of the bottle has been removed, some of the structural integrity is reduced, but the bottom line is: expect some failures here. On the bright side, as you can generally get the bottle for free so the only thing you're wasting here is time, right? When you're all set, you will have something that resembles the pictures above. Keen-eyed observers will note that one of the edges of the lamp body that I cut is not-so-straight. If I were making this into a drinking glass, that would be a problem, but in this case, as this part of the bottle will be covered by either the top or bottom piece of the lamp, and as the not-so-straight edge is not severe enough to impact the sturdiness of the lamp, I let it slide.
Additional considerations: clear glass is going to make for a brighter lamp, but if you're not going to use the green fire type of lamp, colored glass could be attractive. I suspect that it will tend to heat up faster than clear, as it will be absorbing more visible and infrared light, but that's just a theory, and I don't have the means to test it, like a laser thermometer (see resources, above). However, I would try to make the lamp body as long as you can, as this will mean a more gentle temperature gradient between the metal top and the metal bottom. The glass heats up quite a bit (though not as much as the metal top), and if it cracks, you'll have to cut a new piece, which would be lame. Of course the glass is free and all, but still, kinda lame after all that work, right?
Step 3: Cut the Top and Bottom Pieces
At this point, we have a nice glass lamp body, but nothing to hold the light source, and nothing to prevent anything from entering or exiting the lamp. It turns out the outer diameter of the Snapple/Honest Tea bottle fits very snugly inside a standard soup can. I chose the Eden brand bean can because, unlike most other brands, it isn't lined with a BPA-containing plastic. It also has a nice band of non-corrugated steel at the top and bottom. Unfortunately, the corrugated bits shrink the inner diameter just enough to make its use with the glass body unworkable. However, it could work well with a slightly smaller diameter jar, such as the jelly jar I used in the previous step.
I found that the best way to cut the thin steel without deforming it is to use a hacksaw, but not to just try to saw straight through. Fit the hacksaw in the bottom groove of the corrugated section and draw the hacksaw towards you once. Then, rotate the can slightly, and repeat. Keep rotating the can, making one stroke with the saw until you start to wear through the steel. Resist the temptation to just saw straight through until there are little holes developing all around the groove you've cut. When you finally do cut through, the can should really just fall apart. Another benefit of this approach is that the little jags of steel that stick out after you've made the cut are paper-thin, and are less likely to cut you. Note I said "less likely" not "unable."
Clean up the cut with a file (I used a $1 file I got from a Sears bargain bin - nothin' fancy). Drag the file, gently, perpendicular to the edge of the can, bringing up the little metal jags that have gotten folded inside to a vertical position, then file them off by drawing the file parallel to the side of the can. This will go a long way towards cleaning-up the edge.
Finish off with a relatively fine grade of sandpaper - I used super cheap 220 grit. The edge should now be very smooth. If it's still sharp, go over it again, otherwise this next step is gonna suck.
You're going to need to very gently flare out the rim of the can. This is because, although you filed and sanded off most of the indentation from the groove you've cut, there is still some narrowing due to the corrugation. Do this gradually, turning the can while trying to gently "roll" the steel edge outward. If you have something rounded, like a suitably-sized post cap, you can try to use that to flare the edge, but realize that this steel is very thin, and won't take much abuse.
Step 4: Cut the Top and Bottom Piece Vent Holes
If there's going to be fire inside the lamp, we need vent holes in our lamp top. If you're just going for "safe mode" (see below), then you can skip this step. The easiest vent holes would be round, and if that works for you, that's fine. It should be fairly easy to drill or pound a nail through the can lid and thoroughly aerate it. However, I wasn't really feeling round for this part, so I went for the above design. It's slightly more complex than holes, but not so tricky that it would become a project in-and-of-itself. As you can see, I cut this out on a post-it note. It was sort of like making a very simple, eight-sided paper snowflake. Make sure that the form you use fits snugly inside the rim on the top of the can lid. You'll also want to make sure you don't remove too much metal, and weaken the lamp's structural integrity.
As you can see, when I traced it onto the lid, I only used four of the shapes. The others served as guides when I rotated the stencil, and helped make sure that the shapes were drawn in the right places.
The downside to using the entire lid and rim is that you can't really get tin snips in there without totally destroying the top. I figured a jig saw would be too harsh. A coping saw could work, but the utility knife method did a decent job too. The important part is that you will not be cutting the curved bits with the knife. To cut the curves, drill a small hole at the top of each shape. Start with a small bit, and then move up to a larger one. Don't get too big. The drill is generating a lot of torque, and if a large bit catches the metal, it will whip it around and probably tear the strips between the shapes. When the hole gets big enough, remove the metal pieces carefully. These are very sharp, and will make your fingers sad.
Finish up the shapes with a round, small-toothed file and sand smooth. Any excess marker should come off with xylene.
For the bottom piece, round vents worked for me. Drilling or nail pounding did not. The metal is very thin, and as you would be drilling or pounding inside the piece it itself, the chances of tortured and creased metal seemed high. On the bright side, the very fact that the metal was thin made the use of a paper hole-punch tool possible. It worked like a charm, and game me eight, equal-sized holes very rapidly.
Step 5: The Two-Tier Top (Optional)
This part depends on your having another can that is just a bit larger than the first, and has a lip in the top. These are generally found on the "can-opener-free" style of lid used in Campbell's Chunky Soup cans. I actually got mine from the trash at work. The lip on the can creates a nice overhang to which you can attach the vented piece. This part involves a little more trial and error than the other parts. If you don't have anything that works at home, and your co-workers are absurdly health-conscious, you can take the piece you have to the grocery store and attract a lot of stares by holding your art project up to the cans on the shelves to see if they'd make a good fit. You may have to actually eat the contents of the can you purchase, but it's still pretty cheap at the price. Carefully sand off the plastic coating, and sand the lip while you're at it - that thing's sharp! Don't inhale the yucky BPA-laden dust.
Step 6: The Lid
While my little flower (or orange section) design turned out okay, I wanted a lid for two reasons:
1) An extra layer of protection to keep things from falling inside.
2) A pocket of air where (hopefully) the diboron trioxide might end up getting trapped - sort of a boron-baffle.
Also, I wanted something that sort of resembled the old Moroccan-style lamp I had back in college. I decided I would try to sink a piece of steel to make a domed lid. This was my first attempt at sinking metal, and it turned out better than I thought it might. I used a piece cut from an olive oil can because the metal was a little thicker than the soup can metal, and because it was smooth. I didn't have a sinking stump or doming block, but I thought that, given the thinness of the metal, and the curve of the ball peen hammer I was using, I could probably get away with using an old piece of carpet.
The technique is better described many other places, by people who really know what they're doing, but here's the basic idea: start in the middle of a circle of metal and (gently) tap the piece once with a ball peen hammer. Rotate the metal slightly, and strike the metal again, with an equivalent amount of force to the first strike. Keep rotating and striking, moving slowly out toward the edge. The metal will start to curl up, and if you keep going around, will eventually assume the shape of a bowl, or if you turn it over, a dome. If you're working the metal into a dramatically-curved dome, you will probably need to heat the metal until it glows to anneal (or relax) it. Otherwise, it becomes work-hardened, and will be more apt to tear as it thins. I was going for a pretty gentle curve, so I didn't anneal the piece.
A few turns like this and I had ... a brain. At least, it looked kind of like a brain. I trimmed off the excess, and filed it until it fit the top piece of the lamp. And ... it still looked like a brain. I realized I was going to need some way to planish it. Not having a planishing stake, or anything resembling it, I decided I would see if I could approximate it with a fence post cap. Using much lighter taps, I worked systematically around the piece, with it resting on the post cap. The result was something much less brain-like, that actually looked (I thought) kind of cool. I then used the paper hole punch again, and filed the holes with a round file to elongate them a bit. I then sanded them smooth.
The last step was to make a hole in the center of the lid so a handle could be attached. Use a center punch to start the hole, then drill.
Step 7: The Handle
This part is probably the easiest. To make the handle, or nob, or whatever, I sawed the top off of an old-fashioned clothes pin. I actually got mine from Michael's as a craft material, but they're dirt-cheap, and fairly round. My wife insists I should have used a metal finial or a drawer-pull for aesthetic reasons, and there's merit to that. However, the lid of this lamp gets crazy-hot, and this wooden handle is a decent insulator. You could use ceramic or glass, but that wouldn't be so chea ... um ... resourceful, would it?
Anyway, cut off the top of the clothes pin, sand it smooth and stain it to your preferred color. Don't varnish. No sense adding a potential fuel to the situation. I drilled a hole in the piece before I stained so that I could just dip the whole thing in. After the stain has sat on the wood for a few minutes, wipe off the excess and set it somewhere to dry.
Step 8: Solder the Top Assembly (Optional)
Okay, I found this part to be kind of a pain. It's obviously only necessary if you're doing the two-tier top. You need to solder the two pieces together or they tend to slide around and generally comply with the law of gravity by falling apart.
I used lead-free acid core general metal solder. I would imagine that electronics (flux core) solder would tend to react with the steel and make your life miserable, but that's just a guess. The actual metal in the solder is the same - mostly tin with a teeny bit of copper. Because of the size of the area to be soldered, a soldering iron is probably not the way to go. You could use a butane or propane torch (I used the former to help heat the metal), but ultimately, I found putting the whole assembly on a hot plate was the most effective option. This has the added advantage of burning off any resin or plastic coating from the unsanded parts of the pieces.
Cut a piece of solder as long as the outer perimeter of the smaller can lid. Insert the small can lid into the larger lid, and then place the solder in the space between the two cans.
Because melted solder could drip on and generally mess-up your hot plate (obviously that ship has left the station in this case), put a piece of aluminum (or aluminium, depending on where you live) foil under the assembly. To retain as much heat as possible, I placed a pie tin on top.
This took a couple of tries, and a little help from a butane torch, but I don't think that the torch is crucial - just helpful. The hot plate is 1000W and can easily achieve the temperature necessary to heat the pieces and melt the solder. What you don't want to do is to melt the solder without thoroughly heating the assembly, as that results in a "cold joint" which will be very weak. In fact, it probably won't adhere at all. That's one of the main advantages of the hot plate. A toaster oven that you didn't intend to use again for food could also work. I started with the piece face down, and then flipped it over because the inner piece wasn't getting heated enough. I finished with the butane burner, but that was probably overkill.
Please use lead-free solder. Seriously. Lead is the excrement of the devil, to adapt Chavez. If you use leaded solder, every time the lamp heats up, you will be vaporizing a little of the lead, which will then settle everywhere. While there is a wide range of opinions among the scientific and medical communities regarding the safeness of many of the chemicals in our lives, there is tremendous consensus regarding lead. Levels that cause neurological damage are measured in parts per million. That means it's pretty damn toxic.
Step 9: The Two-Tier Bottom (Optional)
Once I had completed the two tier top, the lamp started looking a little aesthetically "unbalanced." I realize that we're talking about tin cans and Snapple bottles here, but still, aesthetics is aesthetics, damn it.
Start with an end piece from the larger can. Make sure that the piece has the "lid" still attached (i.e. the unopened part of the can).
Now, this next part is super optional. I thought that the edges of the can, even with sanding, would have a tendency to scratch any surface on which the lamp rested. Also, given the general thinness of the metal, I wasn't sure how much abuse it could take. As a result, I decided to try to slip the lidded piece inside a piece cut from the other (opened) end of the same can.
To do this, you need to flare out the piece a bit. I used the top of an old gumball machine I had lying around, but any curved surface that is somewhat bigger than can piece should work. With a mallet or hammer, gently tap the uncut side of the work piece down onto your makeshift flaring tool. We're not looking for a big effect here. It just needs to be a little wider than other can.
Once you've flared the piece, file and sand the edge as you have with the other pieces.
Carefully, slip the lidded piece inside the flared piece. There will be some buckling of the inner piece, but it should be pretty invisible from the outside of the assembly.
When you've finished, place the piece on the hot plate to bake off the bad stuff. You can sand it if you like, but I kind of dug the black finish that resulted from the heating process. If you are using a BPA-based plastic, make sure you do this outside, or in a well-ventilated area. In fact, even if you aren't using a BPA-based plastic, do it in a well-ventilated area. Who knows what these compounds break down into?
Side note, the first picture is a repeat of the picture I took of the top. You're cutting the piece in the same way you did the earlier piece, though.
Step 10: Assemble the Base
We're almost there!
The first step is to make a support of the lamp glass. If you don't it will tend to slip down and cover the vent holes. To do this, I used four M6-sized button head bolts with matching hex nuts. These and the standoffs are among the few things I actually had to purchase. You could also use pop rivets, or even make a wire frame to slip inside. However, the method I used seemed sturdy, and had a very small chance of deforming the metal (unlike pop rivets).
Next we need to create something to hold the fire in place. In the end, I went with threaded aluminum spacers. I'm glad that I did, for reasons that will become apparent as we go along
The spacers I used were 3/16" inner diameter, so I bought some 3/16" machine screws. Nothing fancy - just basic galvanized. On the reverse of the top piece of the base assembly I marked out the holes, using a votive candle to work out the locations. I drilled these out, lined up the top and bottom of the base assembly and marked out the drilling locations on the lower piece by tracing through the drilled holes with a fine-tip marker. Drill these out too. It's important that the holes you drill are not too large. You want the screws themselves to hold the assembly together if possible. This will give you more latitude later
Step 11: Version Zero: LED Votive AKA "Safe Mode"
Have unruly kids? A pet moth? Narcolepsy? Experience frequent fugue states? You may want to consider "Safe Mode." Safe mode stops just short of the "votive mode" by using a ... wait for it ... dollar store electric votive! It even sort of flickers! And it's an LED! We love LEDs! It's the same size as a regular votive, so it'll fit right into the holder. Try it out!
Step 12: Version One: Votive
If you're just looking for a unique votive holder, congratulations: you're done! Here's a picture of what our lantern looks like with a votive candle in it.
Step 13: Version Two: The Spirit Lantern
If you're looking for something a little flashier, you can make a handmade alcohol lamp, also known as a spirit lamp. Because this one includes a wind screen, it's a "Spirit Lantern." You can see from my first instructable that this can be made from a sampler-size jelly/jam jar and a piece of wick. I got my jelly jar from a hotel's "complimentary continental breakfast." Christmas samplers are lousy with 'em too.
After removing the label and thoroughly cleaning the jar inside and out, I always remove the paint from the lid. While this is not crucial to the operation of the lamp, it does make me nervous to vaporize the paint on the outside. 220 grit sandpaper and steel wool do the trick.
In my previous lamp, I left the inner seal in place. It hasn't shown any sign of degrading, and I suspect that there's nothing wrong with leaving it there. It's certainly easier to do so, and it forms a much better seal.
However, because I don't particularly like plastic, this time, I decided to remove it. A little acetone made it pretty easy to pull out. I then sanded the remainder of the coating (again, almost certainly BPA-based). Of course, now, there's no seal, and the lid doesn't screw on tightly anymore. We'll fix that in a minute.
Find the center of the lid, mark it with a center punch, and drill. Make sure that the hole you drill doesn't exceed the width of the wick you'll be using. If you drill through the top, rather than the bottom of the lid, there's no need to sand. In fact, sanding will just make it easier for the wick to slid inside, which you don't really want.
Now: the new seal. Cut four disks of paper, sized to fit inside the lid. Match up the hole in the lid to the centers of the disks, and then use the hold punch tool (appropriately for once) to cut holes in them.
To address the question that is hanging out there in the ether: No, the paper doesn't burn.
"But dude," you say. "You just told us that the flame is super hot. What gives?"
What saves those little paper disks from an untimely immolation are the facts that metal is an excellent radiator of heat; heat rises, and inside the jar, alcohol is vaporizing all the time the lamp is lit, thereby drawing heat from its surroundings. All of these factors keep the paper cool enough to save it from a fiery end. At least, that's my theory. If you've got a better one, please share!
Place the disks inside the lid, push the wick through the hole, and voila!
Step 14: Final Assembly and Correction
This is it! Place your lamp inside the standoffs and ... crap. Not enough room. This is what happened to me. Although my jar looked like it was the same size as the votive base, I forgot one thing: the votive base is extremely bendy aluminum, and the jar is rather un-bendy glass. The votive base had distorted slightly while I was marking out the holes, and as a result, when the diameter of the standoffs was thrown into the mix, there was just not enough room for the lamp. Fortunately, this was an easy fix. I just removed one of the standoffs, and left the screw underneath in place. Because the hole I drilled was a snug fit for the screw, the screw stayed in place, and continued to do its job holding the base assembly together. Yay!
Of course, an easy way to avoid this is by making sure that you use your jelly jar lamp to mark out the holes, and of course, to make sure that you take the diameter of the standoffs into account before you drill.
Step 15: Version Two: The Iso-Spirit Lantern
This version uses isopropyl rubbing alcohol as the fuel for the lamp. I recommend that everyone start with this version, because the flame temperature is cooler than that of the methanol version. Why? Because isopropyl alcohol forms what is known as an azeotropic mix with water at 91% purity. This means that it's very hard to come by purer isopropyl alcohol, because dehydrating it further is kind of a pain. As a result, when you burn rubbing alcohol, nearly 1/10th of the liquid is water, and part of the energy released in burning the alcohol goes toward boiling water. You can see this quite easily when you first light your lamp. A haze of water vapor settles on the lamp glass, and stays there until the glass gets too hot for the water to condense on it. Some of this water is certainly a product of combustion, but a significant amount is the 9% water in the solution. When your lamp has heated up, the haze disappears.
On your first lighting, I would recommend letting it go through an entire jar of fuel with the lamp resting in a pan. That way, if the unthinkable occurs, and your lamp breaks, flaming alcohol won't leak out everywhere. And of course, don't ever leave this lamp unattended.
Step 16: Version 3: Green Fire!
This is the real Spirit Lantern. The ghostly green of the green fire is really one of the coolest pyrotechnic experiments you can do in the comfort of your own home. Here's the quick explanation for what does down:
Methanol + Boric Acid = Trimethyl Borate
Not a lot of Trimethyl Borate is created in this reaction, but it's enough to color the pale blue flames of the burning methanol a minty shade of green! For a more complete explanation of the process refer to my first instructable on the subject.
To make the Trimethyl Borate, just dissolve dry boric acid (you can purchase it from a pharmacy) in methanol (aka, the yellow bottle of Heet at your auto supply store). It doesn't take much. Maybe a quarter to an eighth of a teaspoon in a little jam jar like this one. Once the acid is dissolved, screw the lid and wick assembly on. I try to keep my isopropyl alcohol wick and my Trimethyl Borate wicks discrete. Wait a few minutes for the liquid to wick up the wick's fibers. Place the lamp inside the lantern. Light and replace the lamp glass. You did it!
If methanol freaks you out, you can try denatured alcohol. Denatured alcohol is ethyl alcohol (booze) mixed with a small amount of methanol (poison). This is available in hardware stores in big metal cans for not very much money. From what I've read in old chemistry books and seen online, the flame is a less brilliant green. I haven't tried denatured alcohol. Note: Isopropyl alcohol does not work when making green fire.
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